Carbamyl phosphates



United States Patent 3,242,498 CARBAMYL PHOSPHATES Donald G. Stollfey,507 /2 Richmond St., El Cerrito, Califi; Richard C. Maxwell, 1504Clifford St., Pullman, Wash; Arnold D. Gutman, 335 Alcatraz Ave.,Oakland, Calif; Llewellyn W. Fancher, 1662 Foothill Park Circle,Lafayette, Calif.; and James T. Hallett, 20701 St. Charles St.,Saratoga, Calif. No Drawing. Filed Nov. 6, 1962, Ser. No. 235,831

7 Claims. (Cl. 260-938) This invention relates to certain novel chemicalcompounds and to the use of such compounds as insecticides and.acaricides. The compounds are particularly valuable for their systemicand miticidal properties. More specifically the invention relates tocompounds of the formula:

wherein R and R are lower alkyl radicals, R is selected from lower alkyland lower chloroalkyl, X and Y are selected from oxygen and sulfur, atleast one being sulfur, and Z is oxygen or sulfur.

The compounds of the present invention can be made in accordance withthe following illustrative examples: (Code numbers have been assigned toeach compound and are used hereinafter for convenience).

Example 1 Example 2 R-3423Ethyl N 2-(0,0-diethylphosphorodithionyl)ethylcarbamate. In essentially the same manner as Example 1, 7.6 g. ofethyl-N-Z-chloroethyl carbamate was reacted with 12 g. of sodium0,0-diethylphosphorodithioate to give 11.6 g. (77% yield) of a darkamber liquid, N 30 1.4962.

Example 3 -3424Ethyl N-2-(0,0-diethylphosphorothionyl) ethylcarbamate.In essentially the same manner as Example 1, 7.6 g. ofethyl-N-2-chloroethylcarbamate and 12 g. of sodium0,0-diethylphosphorothioate were reacted to give 7 g. (49% yield) of theamber liquid, N 30 1.4547.

Example 4 R35192 chloroethyl-N-Z-(0,0-dimethylphosphorodithiouyl)ethylcarbamate. In essentially the same manner as Example 1, 11 g. ofZ-chloroethyl-N-Z-bromoethylcar-bamate, made by reactingZ-chloroethylchloroformate with aminoethanol and replacing the hydroxygroup with bromide by the means of phosphorus tribrornide, and 12 g. ofsodium 0,0-dimethy1phosphorodithioate were reacted to give 11 g. (71%yield) of the nearly water-white liquid, N BO 1.5164.

Example R-35202 chloroethyl-N-2-(0,0-diethylphosphorodithionyl)ethylcarbamate. In essentially the same manner as Example 1, 11 g. ofchloroethyl-N-Z-bromoethyl- "ice canbamate was reacted with 13 g. ofsodium 0,0-diethylphosphorodithioate to give 14 g. (83% yield) of thewater-white liquid, N 30 1.5123.

Example 6 R-3521-2 chloroethyl-N-2-(0,0-diethylphosphorothionyl)ethylcarbamate. In essentially the same manner as Example 1, 11 g. of2-chloroethyl-N2-bromoethyl c-arbamate was reacted with 13 g. of sodium0,0-diethylphosphorothioate to give 11 g. (69% yield) of the amberliquid, N 30 1.4790.

Example 7 R5992-N B OgO-diethyldithiop'hosphorylethylS-ethylthiolcarbamate. This compound was made by re fluxing. and stirring12.8 g. of N-B-bromoethyl-S-ethylthiolcarbamate and 20.2 g. potassium0,0-diethylphosphorodithioate in cc. of methyl ethyl ketone for twohours. The ketone solvent was then evaporated on a steam bath with air.The residue was then taken up in chloroform, washed 3 times with water,dried over magnesium sulfate, filtered, and the solvent removed on asteam bath with air. The product weighed 16.0 g. (84% yield), ND301.4695.

Example 8 R5994N B 0,0-diethyldithiophosphorylethyl-S-methylthiolcarbamate. This compound was made by refluxing and stirring15.8 g. N-B-brbmoethyl-S-methylthiolcarbamate and 24.6 g. potassium0,0-diethylphosphorodithioate in 100 cc. methyl ethyl ketone for twohours. The ketone solx ent was then evaporated on a steam bath with air.The residue was then taken up in chloroform, washed 3 times with water,dried over magnesium sulfate, filtered, and the solvent removed on asteam bath with air. The product weighed 19.5 g. (81% yield), N 301.5443.

Example 9 R5996N-,3-0,0 diethyldithiophosphorylethyl-S-npropylthiolcarbamate. This compound was made by refluxing andstirring 18.1 g. N-p-bromoethyl-S-n-propylthiolcarbamate and 24.6 g.potassium 0,0-diethylphosphorodithioate in 100 cc. of methyl ethylketone for 2 /2 hours. The ketone solvent was then evaporated on a steambath with air. The residue was then taken up in chloroform, washed 3times with water, dried over magnesiurn sulfate, filtered, and thesolvent removed on a steam bath with air. The product weighed 19.4 g.(73.5% yield), N 3O 1.5368.

Example 10 R-5998N-{3-0,0-diethyldithiop-hosphoryl ethyl S-isopropylthiolcarbamate. This compound was made by refluxing andstirring 18:1 g. N-{3-bromoethyl-S-isopropylthiolcarbamate and 24.6 g.potassium 0,0-diethylphosphorodithioate in cc. methyl ethyl ketone for2% hours. The ketone solvent was then evaporated on a steam bath withair. The residue was then taken up with chloroform, washed 3 times withwater, dried over magnesium sulfate, filtered, and the solvent removedon a steam bath with air. The product weighed 21.0 g. (79.5% yield), N30 1.5330.

The compounds have been tested as insecticides and as acaricidesaccording to the following methods:

Acariciclal evaluation test.The two-spotted mite, Tetranychus telarius(Linn) is employed in tests for acaricides. Young Pinto bean plants areinfested with several hundred mites. Dispersions of test compounds areprepared by dissolving half a gram of the toxic material in tenmilliliters acetone. This solution is then diluted with water containing0.015% Vatsol (a sulfonate type wetting agent) and 0.005% Methocel(methyl 3 i cellulose) as emulsifiers, the amount of water beingsufallowed to air dry and placed in a cardboard mailing tube. ficient togive concentrations of active ingredient rang- Twenty-five female fliesare caged in the tube. The flies ing from 0.25% to 0.005%. The testsuspensions are are continuously exposed to the known residue of thethen sprayed on the infested Pinto bean plants. After active compound inthe cage. After twenty-four and seven and fourteen days, the plants areexamined both 5 seventy-two hours, counts are made to determine livingfor post-embryonic forms of the mite as well as eggs. and dead insects.The LD-SO values are calculated using The precentage of kill isdetermined by comparison with well-known procedures.

HF Roach MWB CFB 28M 28M 28M Code Ug-) (percent) (percent) (percent) PEE Systemic (percent) (percent) (p.p.m.)

1 Percent.

control plants which have not been sprayed and the LD- The compounds ofthe present invention may be applied 50 value calculated usingwell-known procedures. LD- to a pest habitat in the ways well known tothose skilled 50 values are reported under the columns 2 SM in the inthe art such as dusts, sprays of solutions or dispersions table; PEindicates the post-embryonic forms while and the like. E indicates eggs.We claim:

Systemic toxicity evaluation against two-spotted mites. 1. A compound ofthe formula Pinto bean plants are placed in bottles containing 200 ml.of the test solutions and held in place with cotton plugs. 30 X H 0 Onlythe roots are immersed. The solutions are prepared T l PYCH2CH2N C-ZR3by dissolving the test compounds in acetone and then diluting withdistilled water. The final acetone concen- 2 tration of the solutions isnever allowed to exceed 1.0%. As soon as the plants have been placed inthe solutions they are infested with two Spotted mites, Temmychuswherein R and R are lower alkyl radicals, R is selected from the groupconsisting of lower alkyl and lower chlorotelarius. T he results arereported in the table under 2 lk l and X, Y and Z are Selected f thegroup SM Systemic. sisting of oxygen and sulfur, at least one of thegroups After seven and fourteeen days the plants are examined X d Y b511mm both for post-embryonic forms of the mite as well as 2, Thecompound ethyl-N-Z-(0,0-dimethylphosphoroeggs. The percentage of kill isdetermined by comparidi hi l) ethylcarbamate, son with control plantswhich have been placed in dis- 3 Th compound h 1 -2 (O Q di 1 h tilledwater only. Again, the LQ-SO value is calculated di hi l) h l b t andreported under the columns 2 SM Systemic 1n the 4. The compoundethyl-N-2(O,O-diethylpho h table. thionyl) ethylcarbamate.

Insecticidal evaluation testS.F0ur insect species are 5, Th compound Q-hI r ethyI-N-Z-(O O-dimethylsubjected to evaluation tests forinsecticides: phosphorodithionyl) ethylcarbamate.

American cockroach Periplanem 6. The compound2-chloroethyl-N-2-(0,0-diethylph0scana (L1nn.) phorodithionyl)ethylcarbamate.

( Largemi1kW6ed'bug(MWB) oncopeltusfascialus 7. The compound 2chloroethyl-N-Z-(0,0--diethyl- (Dallas) phosphorothionyl)ethylcarbamate.

(3) Confused flour beetle (CFB) Tribolittm confusum (Duval) ReferencesCited by the Examiner (4-) Housefly (HF) Musca domestica (Linn) Theprocedure for the insects is similar to the miticidal UNITED STATESPATENTS testing procedure. Test insects are caged in cardboard 2,630,4513/1953 Fletcher et 260 461 mailing tubes 3%" in diameter and 2%" tall.The 2,743,235 4/1956 MCDeYmOtt 2604161 cages are supplied withcellophane bottoms and screened 2,864,849 12/1958 Schrader 260-451 tops.Ten to twenty-five insects are used per cage. Food 2890947 6/1959Anna'ble et and water are supplied in each cage. The confused flour338x043 4/1963 Beaver at beetles are confined in petri dishes withoutfood, The 3,085,929 4/1963 Haslam 16722 caged insects are sprayed withthe active compound at various concentrations. After twenty-four andseventy- OTHER REFERENCES two hours, counts are made to determine livingand dead MelNikov, -i VOL 52, Column 95 insects. (January 10, 1958).

Housefiy evaluation tests differ in this respect: the toxicant isdissolved in a volatile solvent, preferably acetone, CHARLES PARKERPnmm'y Examine the active compound is pipetted into a petri dish bottom,JULIAN S. LEVITT, Examiner.

1. A COMPOUND OF THE FORMULA